Motor drive control apparatus

Abstract

A motor drive control apparatus includes energization systems for energizing a motor having a plurality of independent winding sets, with the energization systems corresponding one-to-one to the winding sets. A plurality of sensors is provided for each of the energization systems. A controller is provided for each of the energization systems and controls energization of the corresponding winding set based on output signals of the corresponding sensors. A plurality of sub power supply paths is provided for their respective energization systems. Each sub power supply path connects a power supply path for supplying power to the corresponding sensors and a power supply path in another energization system. A semiconductor switch is provided for each of the sub power supply paths, and, between two different energization systems, when one of the two energization systems exhibits a sensor power supply failure, electrically connects the power supply paths of these two energization systems.

The invention claimed is: 
     
       1. A motor drive control apparatus including energization systems for energizing a motor having a plurality of independent winding sets, with the energization systems corresponding one-to-one to the winding sets, the motor drive control apparatus comprising:
 a plurality of sensors which is provided for each of the energization systems and which detects common physical amounts relating to driving control of the motor; 
 a controller which is provided for each of the energization systems and which controls energization of the corresponding winding set based on output signals of the corresponding sensors; 
 a power supply path which is provided for each of the energization systems and which supplies power to the corresponding sensors; 
 a plurality of sub power supply paths, each of which mutually connects the power supply paths of the energization systems; and 
 a semiconductor switch which is provided for each of the sub power supply paths and which, between two different energization systems, when a first energization system, which is one of the two different energization systems, exhibits an abnormality indicating a drop in a voltage of the power supply supplied to the corresponding sensors, electrically connects the power supply path in the first energization system with the power supply path in a second energization system, which is the other one of the two different energization systems. 
 
     
     
       2. The motor drive control apparatus according to  claim 1 , wherein, when the controller in the first energization system detects occurrence of the abnormality in the first energization system based on the output signals of the corresponding sensors in the first energization system, the controller electrically connects the power supply path in the first energization system with the power supply path in the second energization system by controlling the semiconductor switch. 
     
     
       3. The motor drive control apparatus according to  claim 1 , further comprising:
 a monitoring circuit which is provided for each of the energization systems and which monitors a voltage of the corresponding power supply path, 
 wherein, when the controller in the first energization system detects occurrence of the abnormality in the first energization system based on an output signal of the corresponding monitoring circuit, the controller electrically connects the power supply path in the first energization system with the power supply path in the second energization system by controlling the semiconductor switch. 
 
     
     
       4. The motor drive control apparatus according to  claim 1 ,
 wherein at least one of the output signals of the sensors in the second energization system is input to the controller in the first energization system, and 
 wherein, when the controller in the first energization system detects occurrence of the abnormality in the second energization system based on the at least one of the output signals of the sensors in the second energization system, the controller electrically connects the power supply path in the first energization system with the power supply path in the second energization system by controlling the semiconductor switch. 
 
     
     
       5. The motor drive control apparatus according to  claim 1 , wherein the sub power supply path includes a current-limiting resistor which limits a current flowing from the second energization system to the first energization system when the power supply path in the first energization system and the power supply path in the second energization system are electrically connected to each other. 
     
     
       6. The motor drive control apparatus according to  claim 1 ,
 wherein the power supply path in each of the energization systems includes a single common power supply path which is connected to a power supply circuit unique to the corresponding energization system and branch paths which are branched from the common power supply path and which are connected one-to-one to the corresponding sensors, and 
 wherein the sub power supply paths constitute a first sub power supply path which connects one of the branch paths in the first energization system and the common power supply path in the second energization system and a second sub power supply path which connects at least one of the branch paths in the second energization system with the common power supply path in the first energization system. 
 
     
     
       7. The motor drive control apparatus according to  claim 6 , further comprising a backflow prevention mechanism provided on the branch paths in the first energization system and between the corresponding power supply circuit and a connection point of the first sub power supply path to the at least one of the branch paths, to prevent a current that flows from the second energization system to the first energization system via the first sub power supply path from flowing backward to the corresponding power supply circuit. 
     
     
       8. The motor drive control apparatus according to  claim 6 , further comprising a backflow prevention mechanism provided on the common power supply path in the first energization system and between the corresponding sensors and a connection point of the second sub power supply path to the common power supply path in the first energization system, to prevent a current that flows from the second energization system to the first energization system via the first sub power supply path from flowing backward to the corresponding power supply circuit. 
     
     
       9. The motor drive control apparatus according to  claim 6 , further comprising a backflow prevention mechanism provided on the common power supply path in the first energization system and between the corresponding power supply circuit and a connection point of the common power supply path to the second sub power supply path, to prevent a current that flows from the second energization system to the first energization system via the first sub power supply path from flowing backward to the corresponding power supply circuit. 
     
     
       10. The motor drive control apparatus according to  claim 1 , further comprising a self-holding circuit which causes, when the abnormality occurs in the first energization system, the semiconductor switch to maintain the electrical connection between the first energization system and the second energization system, without relying on the controller. 
     
     
       11. The motor drive control apparatus according to  claim 1 ,
 wherein, as the sub power supply paths, a single sub power supply path is provided between the first energization system and the second energization system, and 
 wherein, on the sub power supply path, a first semiconductor switch controllable by the controller in the first energization system and a second semiconductor switch controllable by the controller in the second energization system are provided in parallel to each other. 
 
     
     
       12. A motor drive control apparatus including energization systems for energizing a motor having a plurality of independent winding sets, with the energization systems corresponding one-to-one to the winding sets, the motor drive control apparatus comprising:
 a plurality of sensors which is provided for each of the energization systems and which detects common physical amounts relating to driving control of the motor; and 
 a controller which is provided for each of the energization systems and which controls energization of the corresponding winding set based on output signals of the corresponding sensors, 
 wherein the controller in one of the energization systems receives at least one output signal of the sensors in another energization system different from the one energization system.